.bigBox{
    width: 200px;
    height: 200px;
    background: yellow;
}

.div{
    width: 128px;
    height: 128px;
    float: left;
}

.div1{
    background: url('../assets/images/img1.jpg') no-repeat;
}
.div2{
    background: url('../assets/images/img1.jpg') no-repeat;
}
.div3{
    background: url('../assets/images/img3.jpg') no-repeat;
}
.div4{
    background: url('../assets/images/img4.jpg') no-repeat;
}
.div5{
    background: url('../assets/images/img5.jpg') no-repeat;
}